// -*- mode: js2; indent-tabs-mode: nil; js2-basic-offset: 4 -*-
/* exported enable disable */
const ExtensionUtils = imports.misc.extensionUtils;
const Workspace = imports.ui.workspace;
// testing settings for natural window placement strategy:
const WINDOW_PLACEMENT_NATURAL_ACCURACY = 20; // accuracy of window translate moves (KDE-default: 20)
const WINDOW_PLACEMENT_NATURAL_GAPS = 5; // half of the minimum gap between windows
const WINDOW_PLACEMENT_NATURAL_MAX_TRANSLATIONS = 5000; // safety limit for preventing endless loop if something is wrong in the algorithm
class Rect {
constructor(x, y, width, height) {
[this.x, this.y, this.width, this.height] = [x, y, width, height];
}
// used in _calculateWindowTransformationsNatural to replace Meta.Rectangle that is too slow.
copy() {
return new Rect(this.x, this.y, this.width, this.height);
}
union(rect2) {
let dest = this.copy();
if (rect2.x < dest.x) {
dest.width += dest.x - rect2.x;
dest.x = rect2.x;
}
if (rect2.y < dest.y) {
dest.height += dest.y - rect2.y;
dest.y = rect2.y;
}
if (rect2.x + rect2.width > dest.x + dest.width)
dest.width = rect2.x + rect2.width - dest.x;
if (rect2.y + rect2.height > dest.y + dest.height)
dest.height = rect2.y + rect2.height - dest.y;
return dest;
}
adjusted(dx, dy, dx2, dy2) {
let dest = this.copy();
dest.x += dx;
dest.y += dy;
dest.width += -dx + dx2;
dest.height += -dy + dy2;
return dest;
}
overlap(rect2) {
return !(this.x + this.width <= rect2.x ||
rect2.x + rect2.width <= this.x ||
this.y + this.height <= rect2.y ||
rect2.y + rect2.height <= this.y);
}
center() {
return [this.x + this.width / 2, this.y + this.height / 2];
}
translate(dx, dy) {
this.x += dx;
this.y += dy;
}
}
class NaturalLayoutStrategy extends Workspace.LayoutStrategy {
constructor(settings) {
super();
this._settings = settings;
}
computeLayout(windows, layout) {
layout.windows = windows;
}
/*
* Returns clones with matching target coordinates and scales to arrange windows in a natural way that no overlap exists and relative window size is preserved.
* This function is almost a 1:1 copy of the function
* PresentWindowsEffect::calculateWindowTransformationsNatural() from KDE, see:
* https://projects.kde.org/projects/kde/kdebase/kde-workspace/repository/revisions/master/entry/kwin/effects/presentwindows/presentwindows.cpp
*/
computeWindowSlots(layout, area) {
// As we are using pseudo-random movement (See "slot") we need to make sure the list
// is always sorted the same way no matter which window is currently active.
let areaRect = new Rect(area.x, area.y, area.width, area.height);
let bounds = areaRect.copy();
let clones = layout.windows;
let direction = 0;
let directions = [];
let rects = [];
for (let i = 0; i < clones.length; i++) {
// save rectangles into 4-dimensional arrays representing two corners of the rectangular: [left_x, top_y, right_x, bottom_y]
let rect = clones[i].metaWindow.get_frame_rect();
rects[i] = new Rect(rect.x, rect.y, rect.width, rect.height);
bounds = bounds.union(rects[i]);
// This is used when the window is on the edge of the screen to try to use as much screen real estate as possible.
directions[i] = direction;
direction++;
if (direction === 4)
direction = 0;
}
let loopCounter = 0;
let overlap;
do {
overlap = false;
for (let i = 0; i < rects.length; i++) {
for (let j = 0; j < rects.length; j++) {
let adjustments = [-1, -1, 1, 1]
.map(v => (v *= WINDOW_PLACEMENT_NATURAL_GAPS));
let iAdjusted = rects[i].adjusted(...adjustments);
let jAdjusted = rects[j].adjusted(...adjustments);
if (i !== j && iAdjusted.overlap(jAdjusted)) {
loopCounter++;
overlap = true;
// TODO: something like a Point2D would be nicer here:
// Determine pushing direction
let iCenter = rects[i].center();
let jCenter = rects[j].center();
let diff = [jCenter[0] - iCenter[0], jCenter[1] - iCenter[1]];
// Prevent dividing by zero and non-movement
if (diff[0] === 0 && diff[1] === 0)
diff[0] = 1;
// Try to keep screen/workspace aspect ratio
if (bounds.height / bounds.width > areaRect.height / areaRect.width)
diff[0] *= 2;
else
diff[1] *= 2;
// Approximate a vector of between 10px and 20px in magnitude in the same direction
let length = Math.sqrt(diff[0] * diff[0] + diff[1] * diff[1]);
diff[0] = diff[0] * WINDOW_PLACEMENT_NATURAL_ACCURACY / length;
diff[1] = diff[1] * WINDOW_PLACEMENT_NATURAL_ACCURACY / length;
// Move both windows apart
rects[i].translate(-diff[0], -diff[1]);
rects[j].translate(diff[0], diff[1]);
if (this._settings.get_boolean('use-more-screen')) {
// Try to keep the bounding rect the same aspect as the screen so that more
// screen real estate is utilised. We do this by splitting the screen into nine
// equal sections, if the window center is in any of the corner sections pull the
// window towards the outer corner. If it is in any of the other edge sections
// alternate between each corner on that edge. We don't want to determine it
// randomly as it will not produce consistant locations when using the filter.
// Only move one window so we don't cause large amounts of unnecessary zooming
// in some situations. We need to do this even when expanding later just in case
// all windows are the same size.
// (We are using an old bounding rect for this, hopefully it doesn't matter)
let xSection = Math.round((rects[i].x - bounds.x) / (bounds.width / 3));
let ySection = Math.round((rects[i].y - bounds.y) / (bounds.height / 3));
iCenter = rects[i].center();
diff[0] = 0;
diff[1] = 0;
if (xSection !== 1 || ySection !== 1) { // Remove this if you want the center to pull as well
if (xSection === 1)
xSection = directions[i] / 2 ? 2 : 0;
if (ySection === 1)
ySection = directions[i] % 2 ? 2 : 0;
}
if (xSection === 0 && ySection === 0) {
diff[0] = bounds.x - iCenter[0];
diff[1] = bounds.y - iCenter[1];
}
if (xSection === 2 && ySection === 0) {
diff[0] = bounds.x + bounds.width - iCenter[0];
diff[1] = bounds.y - iCenter[1];
}
if (xSection === 2 && ySection === 2) {
diff[0] = bounds.x + bounds.width - iCenter[0];
diff[1] = bounds.y + bounds.height - iCenter[1];
}
if (xSection === 0 && ySection === 2) {
diff[0] = bounds.x - iCenter[0];
diff[1] = bounds.y + bounds.height - iCenter[1];
}
if (diff[0] !== 0 || diff[1] !== 0) {
length = Math.sqrt(diff[0] * diff[0] + diff[1] * diff[1]);
diff[0] *= WINDOW_PLACEMENT_NATURAL_ACCURACY / length / 2; // /2 to make it less influencing than the normal center-move above
diff[1] *= WINDOW_PLACEMENT_NATURAL_ACCURACY / length / 2;
rects[i].translate(diff[0], diff[1]);
}
}
// Update bounding rect
bounds = bounds.union(rects[i]);
bounds = bounds.union(rects[j]);
}
}
}
} while (overlap && loopCounter < WINDOW_PLACEMENT_NATURAL_MAX_TRANSLATIONS);
// Work out scaling by getting the most top-left and most bottom-right window coords.
let scale;
scale = Math.min(
areaRect.width / bounds.width,
areaRect.height / bounds.height,
1.0);
// Make bounding rect fill the screen size for later steps
bounds.x -= (areaRect.width - bounds.width * scale) / 2;
bounds.y -= (areaRect.height - bounds.height * scale) / 2;
bounds.width = areaRect.width / scale;
bounds.height = areaRect.height / scale;
// Move all windows back onto the screen and set their scale
for (let i = 0; i < rects.length; i++)
rects[i].translate(-bounds.x, -bounds.y);
// rescale to workspace
let slots = [];
for (let i = 0; i < rects.length; i++) {
rects[i].x = rects[i].x * scale + areaRect.x;
rects[i].y = rects[i].y * scale + areaRect.y;
slots.push([rects[i].x, rects[i].y, scale, clones[i]]);
}
return slots;
}
}
let winInjections, workspaceInjections;
function resetState() {
winInjections = { };
workspaceInjections = { };
}
function enable() {
resetState();
let settings = ExtensionUtils.getSettings();
workspaceInjections['_getBestLayout'] = Workspace.Workspace.prototype._getBestLayout;
Workspace.Workspace.prototype._getBestLayout = function (windows) {
let strategy = new NaturalLayoutStrategy(settings);
let layout = { strategy };
strategy.computeLayout(windows, layout);
return layout;
};
// position window titles on top of windows in overlay
winInjections['relayout'] = Workspace.WindowOverlay.prototype.relayout;
Workspace.WindowOverlay.prototype.relayout = function (animate) {
if (settings.get_boolean('window-captions-on-top')) {
let [, , , cloneHeight] = this._windowClone.slot;
this.title.translation_y = -cloneHeight;
}
winInjections['relayout'].call(this, animate);
};
}
function removeInjection(object, injection, name) {
if (injection[name] === undefined)
delete object[name];
else
object[name] = injection[name];
}
function disable() {
var i;
for (i in workspaceInjections)
removeInjection(Workspace.Workspace.prototype, workspaceInjections, i);
for (i in winInjections)
removeInjection(Workspace.WindowOverlay.prototype, winInjections, i);
global.stage.queue_relayout();
resetState();
}